The Air Compressor is the general core air source equipment for industrial production, engineering construction, mine operation and equipment maintenance, mainly providing stable compressed air for pneumatic tools, mechanical braking, control system and purging equipment. When selecting air compressor, many users only pay attention to the price and model size, and ignore the working condition matching, pressure flow, power form, stability and durability, resulting in insufficient air supply, frequent failures, high energy consumption and failure to adapt to the field operation requirements. In order to help enterprises to accurately select models and avoid procurement misconceptions, this paper introduces scientific selection methods and precautions for use of air compressors in combination with industrial general scenes, and adapts to various scenes such as factory supporting, engineering machinery and Generator set supporting. 1、 Determine the type of aircraft according to the use scenario
The first step in air compressor selection is to distinguish the use scenarios. Different working conditions correspond to different models, structures and working modes, and mismatching will directly affect the operation efficiency. At present, the main air compressor is divided into piston type and screw type. Piston air compressor is featured by simple structure, high cost performance, flexible start and stop, suitable for intermittent operation and small gas demand. It is commonly used for temporary gas consumption on site, daily purging of equipment, small pneumatic tool operation, low start and stop frequency and short operation time.
The screw air compressor features large air output, stable air supply and 24h continuous operation. It is suitable for the plant assembly line and large unit supporting and long-term uninterrupted air supply. It can stably output constant pressure air source, with small pressure fluctuation and low noise. In addition, according to the power form, it can be divided into motor drive and engine drive. For the plant area with stable mains supply, the motor type is preferred; Industrial air compressors driven by engines are preferred for field sites, mines and scenes without mains supply, which are suitable for outdoor operation without power grid.
2、 Precise calculation of gas volume and pressure to match equipment demand
Pressure and air displacement are the core parameters of air compressor model selection, and also the most easily selected indicators. The user needs to calculate according to the total demand of all gas equipment on site, including the total flow of pneumatic tools working at the same time, control air, purging air, etc. During model selection, 15% - 20% air volume allowance shall be reserved to avoid insufficient air supply and pressure drop caused by full-load operation.
In terms of pressure, conventional industrial pneumatic tools, equipment purging and common braking systems are suitable for 0.8MPa standard pressure; Heavy machinery, mine equipment, high pressure pneumatic devices require higher pressure models. Avoid "large load of small machine". Long-term overload operation will lead to high temperature, frequent start and stop of the main machine and greatly shorten the service life; At the same time, it is not recommended to blindly purchase oversized models, which will cause waste of energy consumption, idle equipment and increase the procurement and operation and maintenance costs.
3、 Different working conditions and environments, suitable for dust and high temperature resistance
Different operating environments have great differences in the durability requirements of air compressors. The construction site, mining area and field have large dust and high temperature, so the requirements for dust prevention, heat dissipation and high temperature resistance of equipment are higher. Attention shall be paid to the protection grade, air intake filtration system and heat dissipation structure of the complete machine during purchase. Under severe working conditions, the model with multi-layer air intake filtration configuration is preferred, which can effectively block the dust and impurities and prevent the dust from entering the host to cause wear, carbon deposition and clamping stagnation.
In high temperature summer, enclosed plant and outdoor exposure environment, it is required to confirm whether the equipment cooling air duct, fan configuration and body cooling structure are reasonable to avoid high temperature shutdown and frequent triggering of high temperature protection. Pay attention to the anti-rust and electrical waterproof capacity of the whole machine in wet environment to prevent the circuit from being affected with damp. For clean and constant temperature standard plant, conventional standard model can be selected to meet stable air supply.
4、 Check core configuration and judge equipment durability
The service life and stability of the air compressor completely depend on the main engine, motor, oil circuit, control system and other core configurations. When selecting, do not just look at the appearance, but focus on the process of the main machine head. The head is the core component of the air compressor, which determines the exhaust efficiency and service life. The high-quality head operates stably, with low noise and vibration, and is not easy to be worn for a long time.
At the same time, check the oil circuit system to confirm that the engine oil lubrication, oil filter and oil-gas separation are complete. A good lubrication system can reduce the head wear, reduce high temperature faults and extend the maintenance period. The electric control system shall be equipped with overload protection, phase loss protection, high temperature protection, automatic start and stop functions, and can automatically shut down the protection equipment under abnormal working conditions. The air storage tank shall comply with the pressure bearing standard of national standard, with uniform weld joint and no deformation, eliminating potential pressure bearing hazards and guaranteeing the operation safety of the complete machine.
5、 Easy maintenance model shall be selected based on operation and maintenance cost
Many low-price air compressors have low procurement cost, but frequent maintenance in later period, difficult to find parts, high failure rate and higher long-term operation and maintenance cost. For model selection, priority shall be given to the model with mature structure, universal accessories and convenient maintenance. Focus on confirming that the air filter, oil filter, engine oil, sealing parts and other conventional wearing parts are universal, convenient for later replacement and cost controllable.
At the same time, pay attention to the intelligent degree of the equipment. The model with automatic pressure regulation, automatic drainage and fault self-inspection functions can reduce manual intervention, prompt the maintenance period and fault problems in time, and reduce the shutdown risk. For the enterprise scenario of long-term continuous operation, the industrial model with long service life and low failure rate is preferred to reduce the production loss caused by shutdown maintenance.
6、 Code use and foundation selection principles
The correct model shall be used in a standardized manner. Before the new machine is put into use, special engine oil for the air compressor shall be added. Check the tightness of the belt, the tightness of the pipeline and the state of the drain valve of the air storage tank. Before operation, conduct no-load operation and preheating, and confirm that the pressure rises stably without abnormal sound and air leakage. Avoid long-term overpressure operation and frequent startup and shutdown during operation, and adjust the pressure reasonably according to the gas demand. Drain water in time after shutdown every day, replace the filter element and engine oil regularly, and keep the air intake clean and sufficiently lubricated.
The core logic of overall model selection is: piston type for small air volume intermittent working condition and screw type for continuous and stable air supply; Electric motor type is selected for indoor mains supply, and engine drive type is selected for outdoor non-electric supply; Under severe working conditions, industrial equipment with high protection, strong heat dissipation and multi-filtration configuration shall be preferred. The stable operation, controllable energy consumption and long service life of the equipment can only be realized by reasonably matching the scenario, pressure and flow.
